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Anti-wrinkle die of cnc tube bending machine
Bending quality is always a very important point for products manufacturers and wrinkles at inner part of the bent pipes is a headache for many cnc tube bending machine operators. To help our clientes to obtain high bending quality we improved our cnc tube bending machines for sale. Not only in control systema but also in cnc copper tube bending machine dies. We apply a especial disigned 3 axis cnc tube bending machine die-- anti-wrinkle die, to prevent forming of wrinkles on pipes.
● Causes of wrinkles on pipes when do bending work with cnc tube bending machines
Tube bending cnc pipe bending machine’s bending procedures are the followings:
1. Pressure die, bending die and clamping die of cnc tube bender machine hold the pipe firmly.
2. The bending die of cnc tube and pipe bender rotates around its central axis, at the same time the pipe is forced to move together with the bending die, thus, the pipe is wraped.
With movements of cnc steel pipe bending machine dies, the pipe undergoes plastic deformation. The material inside of the center-line of the tube is compressed when a tube is being bent by a cnc tube bending machine. When the tube is bent to a certain angle, the material will be pushed back due to the high compression force of material of the tube. If the pipe wall in this area is not supported by any cnc tube bending machines dies, it’s possible to form wrinkles in this area. This phenomenon appears more times when we bend stainless steel pipes. The solution of this problem is to install anti-wrinkle die on the cnc hydraulic tube bender. The anti-wrinkle die can support this area and prevent wrinkles. This solution is the same for cnc small tube bending machine and big tube bending machine.
● Shape of anti-wrinkle die and its position on cnc tube benders
The shape and measurement of cnc tube bending machines anti-wrinkle die is specially designed. The groove of the anti-wrinkle die through which the pipe slides is slightly larger than the outer diameter of the pipe: about 10% of the wall thickness wider than the pipes. This can guarantee that the pipe can slide through the anti-wrinkle die of cnc tube bender machine but can’t wobble violently.
The groove also needs to be polished carefully to prevent from scratching the surface of the pipe. The front section of anti-wrinkle die of 3 axis cnc tube bending machine is very thin so that can extend to the tangent point of the bending die and lean lightly on the bending die. The anti-wrinkle die is fixed to the tube bending cnc pipe bending machine by screws and nuts. To adjust the anti-wrinkle die on the tube bending cnc pipe bending machine, the pressure die should be well installed and offer proper pressure. It’s also necessary the use of clamping die and mandrel for the adjustment of the anti-wrinkle die.
● Precautions for use of anti wrinkle die on cnc tube benders for sale
When the cnc copper tube bending machine does bending work with anti-wrinkle die, it’s better to smear appropriate amount of lubricating oil on the groove of anti-wrinkle die to help the pipe to slide smooth through the groove. But, too much lubricating oil on the anti-wrinkle die will lead to skid of the pipe and wrinkles on the pipe.
The cnc copper tube bender is often equipped with anti-wrinkle die and mandrel at the same time to achieve good bending result. The anti-wrinkle die and mandrel of a cnc copper tube bender have different functions. The anti-wrinkle die is used to prevent wrinkles; and the mandrel can keep the tube from collapsing after bending.
The following points should be paid attention to in order to avoid wrinkles on pipes when bend pipes with thin wall, large diameter and small bending radius with cnc tube bending machines:
① Reduce friction between cnc mandrel tube bender mandrel and the inner wall of the pipe during bending. Clean the pipe before bending: using wet abrasive blasting to clear the inner cavity of the pipe before putting it on the cnc tube bending machine china.
②The frame and main axis of the cnc tube bender for sale should be rigid enough to bear the strength of bending.
③The cnc mandrel tube bender rod should be rigid enough to eliminate the shaking and stretching of the rod during bending process.
④The radial clearance between 3 axis cnc tube bender mandrel and the inner diameter of pipe shouldn’t be greater than 10% of the wall thickness.
⑤The clamping die, pressing die, mandrel and anti-wrinkle die of the cnc tube bending machine china should be adjusted properly. In particular, the pressure of clamping die should be carefully adjusted.
⑥The clamping force of clamping die of cnc tube bending machines for sale is also very important for the bending quality when bend pipes with large diameter. In this case, the straight line between the two bends of the pipe needs to be long enough so that the clamping die can be wide enough to clamp the pipe firmly during the bending process. If the clamping die of the cnc tube bending machines for sale is short, it cannot hold the pipe pipe firmly. The pipe will skid during the bending process.
As one of the most reliable cnc tube bending machine manufacturers in China, YANSUMI MACHINERY not only provide high-quality hydraulic pipe benders, large and small cnc tube bender for customers all over the world, but also cnc tube bending machines knowledge to help our customers to get better bending results.
